The gaseous effluents from the manufacturing of semiconductor materials, devices, products and memory articles involve a wide variety of chemical compounds used and produced in the process facility. These compounds include inorganic and organic compounds, breakdown products of photo-resist and other reagents, and a wide variety of other gases that must be removed from the waste gas before being vented from the process facility into the atmosphere.
Semiconductor manufacturing processes utilize a variety of chemicals, many of which have extremely low human tolerance levels. Such materials include gaseous hydrides of antimony, arsenic, boron, germanium, nitrogen, phosphorous, silicon, selenium, silane, silane mixtures with phosphine, argon, hydrogen, organosilanes, halosilanes, halogens, organometallics and other organic compounds.
Halogens, e.g., fluorine (F2) and other fluorinated compounds, are particularly problematic among the various components requiring abatement. The electronics industry uses perfluorinated compounds (PFCs) in wafer processing tools to remove residue from deposition steps and to etch thin films. PFCs are recognized to be strong contributors to global warming and the electronics industry is working to reduce the emissions of these gases. The most commonly used PFCs include, but are not limited to, CF4, C2F6, SF6, C3F8, C4H8, C4H8O and NF3. In practice, these PFCs are dissociated in a plasma to generate highly reactive fluoride ions and fluorine radicals, which do the actual cleaning and/or etching. The effluent from these processing operations include mostly fluorine, silicon tetrafluoride (SiF4), hydrogen fluoride (HF), carbonyl fluoride (COF2), CF4 and C2F6.
Improved methods and apparatus for abating such effluent streams are desired.